This presentation by Juan Gonzalez provides new evidence on a major geologic event that took place 27 million years ago, the deposition of the Catahoula Volcanic Ash. Ramifications of this important event include, the formation of the petrified forest in Starr County, the occurrence of Uranium in South Texas, and the genesis of El Sauz chert, an important lithic resource used in prehistory by the early inhabitants of the Rio Grande Valley for stone tool making.
By Juan L. Gonzalez & Roseann Bacha-Garza